The use of microchannel plates has greatly improved image intensifier tubes. These plates consist essentially of a large number of uniform electron multiplier channels the input and output apertures of which match the minimum resolution of the image intensifier. In addition to being more compact than other types of electron optics, these plates are inherently self limiting to prevent blooming and related effects. Although the image intensifier tube walls may both be made of vitreous or ceramic material, the requirement for electrical connections has resulted in complicated structures with multiple metal contacts sealed through the tube walls. Not only are these structures costly, but they are prone to failure through loss of vacuum.